Imbus/kernelmod_demo
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Imbus 2026-02-24 13:49:54 +01:00
parent 04b82dab30
commit 0657191cf0
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ioctl_chardev/my-ioctl.c Normal file
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#include <linux/device.h>
#include "my-ioctl.h"
MODULE_DESCRIPTION("Chardev Ioctl kernel module.");
MODULE_VERSION("0.0.1");
MODULE_AUTHOR("Imbus");
MODULE_LICENSE("GPL");
#define DEVICE_NAME "hello_ioctl"
static int major; /* Dynamically assigned */
static struct class *cls;
static long my_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
/* See: https://elixir.bootlin.com/linux/v6.14.5/source/include/linux/fs.h#L2131 */
static struct file_operations fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = my_ioctl,
};
static long my_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
pr_info("Ioctl called by %s...\n", current->comm);
switch (cmd) {
case MY_IOCTL_FILL:
pr_info("Ioctl FILL by %s...\n", current->comm);
break;
case MY_IOCTL_WIPE:
pr_info("Ioctl WIPE by %s...\n", current->comm);
break;
default:
return -ENOTTY; // Invalid command
}
return 0;
}
static int __init demo_mod_init(void)
{
major = register_chrdev(0, DEVICE_NAME, &fops);
if (major < 0) {
pr_info(DEVICE_NAME " - Error registering chrdev\n");
return major;
}
pr_info(DEVICE_NAME " was assigned major number %d.\n", major);
cls = class_create(DEVICE_NAME);
device_create(cls, NULL, MKDEV(major, 0), NULL, DEVICE_NAME);
pr_info(DEVICE_NAME " created on /dev/%s\n", DEVICE_NAME);
pr_info(DEVICE_NAME " major nbr %d loaded successfully...\n", major);
return 0;
}
static void __exit demo_mod_exit(void)
{
device_destroy(cls, MKDEV(major, 0));
class_destroy(cls);
unregister_chrdev(major, DEVICE_NAME);
pr_info(DEVICE_NAME " unloaded successfully...\n");
}
module_init(demo_mod_init);
module_exit(demo_mod_exit);